Pulsed laser deposited Cr-doped CoFe2O4 thin film as highly efficient oxygen evolution reaction electrode

•CFO and CCFO electrodes were synthesized by pulsed laser deposition (PLD).•The composition of products can be easily tuned.•The OER activity highly depends on the Cr doping.•The overpotential of CCFO electrode is 293 mV with a Tafel slope 76 mV/dec.•CCFO electrode shows excellent durability and stability.